This working paper is part of the research project, The Evolution of Residential Land Use Regulation in Greater Boston, carried out under the auspices of Harvard’s Joint Center for Housing Studies and the Rappaport Institute for Greater Boston. The goals of this project are to identify and understand the reasons that towns and cities in eastern Massachusetts have made Greater Boston a highly regulated urban region and to help devise residential planning policies that advance general, rather than parochial, interests, and what some call "Smart Growth." In particular, the project aims to discover precisely why and under what circumstances particular communities adopted residential land use regulations by studying the evolution of regulations in residential real estate development in four different Boston-area communities and in the legal interpretation of the state laws of Massachusetts.